DESCRIPTION: Rapamycin is an immunosuppressant that acts by inhibiting cytokine dependent proliferation of cells and binds to a cytosolic receptor termed FKBP12. This research will investigate whether a recently described protein termed RAFT1 or FRAP has a role for the biological effects of rapamycin. In Phase I, the role of RAFT1/FRAP in regulating S6 kinase activity will be investigated by under-expressing or over-expressing the protein in a variety of cell lines. A second series of experiments will determine whether RAFT1/FRAP has a role in cell cycle regulation. A committee will be established to monitor the applicant's progress, and transition to Phase II of the training. A structured career development plan is proposed to insure the candidate's successful transition to a fully independent investigator.